Field of the Invention
The present invention relates to a medical manipulator and a treatment tool replacement method. More specifically, the present invention relates to a medical manipulator in which a plurality of replaceable treatment tools are mounted and used, and a treatment tool replacement method in the medical manipulator.
Description of Related Art
Conventionally, it is known that a medical manipulator includes various types of treatment tools detachably attached to a body thereof, and the treatment tools are properly selected according to a procedure to be performed, target tissue, etc. so as to be mounted to the body and used. For example, PCT International Publication No. WO 2010/126127 discloses a medical manipulator in which a body having a drive section and a work section equivalent to a treatment tool are detachably attached to each other.
Among treatment tools of a medical manipulator, there is a treatment tool in which a bending section is provided at a distal end side thereof and bent in a desired direction by operation of an operation member such as a wire using a drive section, so as to perform a procedure. Accordingly, in order to allow a curved state of the treatment tool to correspond to the operation of a practitioner with high accuracy, the drive section needs to engage with the treatment tool in a state in which their phases coincide. However, when the treatment tool is removed from a body for replacement, a shaft of the drive section or the like is in a free state due to the release of the engagement and may thus rotate due to self-weight or the like. When another treatment tool is mounted after occurrence of such rotation, the phases do not coincide. As a result, there is a problem in that correspondence accuracy between the state of the treatment tool and the operation of the practitioner deteriorates.
In consideration of the above problem, the medical manipulator of PCT International Publication No. WO 2010/126127 is configured such that a drive section side engagement section is provided with a detection pin advancing and retracting in an axial direction of a drive shaft and a work section side engagement section is provided with a cam surface having a height changed in an axial direction in a circumferential direction. The medical manipulator is provided with a sensor for detecting a position of the detection pin changed by abutting the cam surface, thereby allowing a phase of the work section side to be detected at the drive section side in an interconnected state.
Accordingly, even though the drive section is attached to the work section in a state in which their phases are deviated from each other when the work section is replaced or remounted, a phase difference between the drive section side and the work section side can be detected. Accordingly, angle correspondences (phases) between the drive section and the work section can be made to coincide by performing correction of the detected phase difference.